Most people tend to overeat given a generous supply of appetising food, but some don’t put on weight while others do. Sadaaf Farooqi, professor of Metabolism and Medicine at Cambridge investigates the genetics of obesity, the brain’s response to food and how hormones influence metabolism and weight. Many myths surrounding weight gain such as a slow metabolism or, it’s my genes doctor, turn out to be true.

So should we be more compassionate to people who struggle with their weight?

In front of an audience of London Sixth formers at the Wellcome Collection she tells Claudia Hammond how only eating an extra slice of cucumber per day could cause an increase in weight.

(Photo: Statue to illustrate obesity - I Cannot Help the Way I Feel by John Isaacs. Credit: Wellcome Collection) Show less